Clarification Process of Ginger Juice with Ultrasonic Assisted Attapulgite-chitosan by Response Surface Methodology

The effect of ultrasonic treatment on the clarification of ginger juice was investigated and the clarification process was optimized by using attapulgite and chitosan as compound clarifier. And,the effects of different clarification methods on the clarification effect and quality of ginger juice were compared with color,light transmittance,soluble solids contents,total phenol contents,gingerol contents and protein contents. Results showed that the optimum conditions of ultrasonic assisted attapulgite-chitosan compound for clarifying ginger juice were as follows:Ultrasonic time 10 min,ultrasonic temperature 54℃ and ultrasonic power 160 W. The light transmittance of ginger juice was more than 96.78%±0.56% under this condition. Comparing with different clarification methods,the ginger juice clarified by ultrasonic assisted attapulgite-chitosan compound clarifier had light color,high light transmittance and highest gingerol contents,and the differences were significant(P<0.05). However,the contents of total phenols and protein which affect the stability of ginger juice was the lowest,which was significantly(P<0.05)different from the other three methods. And the contents of soluble solids was not different from other methods.